Barn Repair

链接

分析：我们不断统计相邻两个元素之间的差值，按照差值从大到小排序，在进行贪心即可

/*
    PROB:barn1
    ID:wanghan
    LANG:C++
*/
#include "iostream"
#include "cstdio"
#include "cstring"
#include "string"
#include "cmath"
#include "algorithm"
using namespace std;
const int maxn=220;
int m,s,c;
int stall[maxn];
struct  Node
{    
    int sub,id;    
};
Node p[maxn];
bool cmp(Node x,Node y){
    return x.sub>y.sub;
}
int vis[maxn];
int main()
{
    freopen("barn1.in", "r", stdin);  
    freopen("barn1.out", "w", stdout);
    cin>>m>>s>>c;
    for(int i=0;i<c;i++){
        cin>>stall[i];
    }
    sort(stall,stall+c);
    for(int i=1;i<c;i++){
        p[i].id=i;
        p[i].sub=stall[i]-stall[i-1];
    }
    //p[c].id=c;
    //p[c].sub=s-stall[c-1];
    sort(p+1,p+c,cmp);
    if(m>=c){
        cout<<c<<endl;
    }else{
        int cnt=stall[c-1]-stall[0];
        //cout<<cnt<<endl;
        for(int i=1;i<m;i++){
            cnt-=p[i].sub;
            //cout<<"sub:"<<p[i].sub<<endl;
            //cout<<cnt<<endl;
        }
        cout<<cnt+m<<endl;
    }
}